iscsi-target: Initial traditional TCP conversion to iscsit_transport

This patch performs the initial conversion of existing traditional iscsi
to use iscsit_transport API callers.  This includes:

- iscsi-np cleanups for iscsit_transport_type
- Add iscsi-np transport calls w/ ->iscsit_setup_up() and ->iscsit_free_np()
- Convert login thread process context to use ->iscsit_accept_np() for
  connections with pre-allocated struct iscsi_conn
- Convert existing socket accept code to iscsit_accept_np()
- Convert login RX/TX callers to use ->iscsit_get_login_rx() and
  ->iscsit_put_login_tx() to exchange request/response PDUs
- Convert existing socket login RX/TX calls into iscsit_get_login_rx()
  and iscsit_put_login_tx()
- Change iscsit_close_connection() to invoke ->iscsit_free_conn() +
  iscsit_put_transport() calls.
- Add iscsit_register_transport() + iscsit_unregister_transport() calls
  to module init/exit

v4 changes:

- Add missing iscsit_put_transport() call in iscsi_target_setup_login_socket()
  failure case

v2 changes:

- Update module init/exit to use register_transport() + unregister_transport()
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

drivers/target/iscsi/iscsi_target.c

@@ -49,6 +49,8 @@
 #include "iscsi_target_device.h"
 #include "iscsi_target_stat.h"
 
+#include <target/iscsi/iscsi_transport.h>
+
 static LIST_HEAD(g_tiqn_list);
 static LIST_HEAD(g_np_list);
 static DEFINE_SPINLOCK(tiqn_lock);
@@ -401,8 +403,7 @@ struct iscsi_np *iscsit_add_np(
 	spin_unlock_bh(&np_lock);
 
 	pr_debug("CORE[0] - Added Network Portal: %s:%hu on %s\n",
-		np->np_ip, np->np_port, (np->np_network_transport == ISCSI_TCP) ?
-		"TCP" : "SCTP");
+		np->np_ip, np->np_port, np->np_transport->name);
 
 	return np;
 }
@@ -441,11 +442,10 @@ int iscsit_reset_np_thread(
 	return 0;
 }
 
-static int iscsit_del_np_comm(struct iscsi_np *np)
+static void iscsit_free_np(struct iscsi_np *np)
 {
 	if (np->np_socket)
 		sock_release(np->np_socket);
-	return 0;
 }
 
 int iscsit_del_np(struct iscsi_np *np)
@@ -467,20 +467,32 @@ int iscsit_del_np(struct iscsi_np *np)
 		send_sig(SIGINT, np->np_thread, 1);
 		kthread_stop(np->np_thread);
 	}
-	iscsit_del_np_comm(np);
+
+	np->np_transport->iscsit_free_np(np);
 
 	spin_lock_bh(&np_lock);
 	list_del(&np->np_list);
 	spin_unlock_bh(&np_lock);
 
 	pr_debug("CORE[0] - Removed Network Portal: %s:%hu on %s\n",
-		np->np_ip, np->np_port, (np->np_network_transport == ISCSI_TCP) ?
-		"TCP" : "SCTP");
+		np->np_ip, np->np_port, np->np_transport->name);
 
+	iscsit_put_transport(np->np_transport);
 	kfree(np);
 	return 0;
 }
 
+static struct iscsit_transport iscsi_target_transport = {
+	.name			= "iSCSI/TCP",
+	.transport_type		= ISCSI_TCP,
+	.owner			= NULL,
+	.iscsit_setup_np	= iscsit_setup_np,
+	.iscsit_accept_np	= iscsit_accept_np,
+	.iscsit_free_np		= iscsit_free_np,
+	.iscsit_get_login_rx	= iscsit_get_login_rx,
+	.iscsit_put_login_tx	= iscsit_put_login_tx,
+};
+
 static int __init iscsi_target_init_module(void)
 {
 	int ret = 0;
@@ -557,6 +569,8 @@ static int __init iscsi_target_init_module(void)
 		goto ooo_out;
 	}
 
+	iscsit_register_transport(&iscsi_target_transport);
+
 	if (iscsit_load_discovery_tpg() < 0)
 		goto r2t_out;
 
@@ -587,6 +601,7 @@ static void __exit iscsi_target_cleanup_module(void)
 	iscsi_deallocate_thread_sets();
 	iscsi_thread_set_free();
 	iscsit_release_discovery_tpg();
+	iscsit_unregister_transport(&iscsi_target_transport);
 	kmem_cache_destroy(lio_cmd_cache);
 	kmem_cache_destroy(lio_qr_cache);
 	kmem_cache_destroy(lio_dr_cache);
@@ -4053,6 +4068,12 @@ int iscsit_close_connection(
 
 	if (conn->sock)
 		sock_release(conn->sock);
+
+	if (conn->conn_transport->iscsit_free_conn)
+		conn->conn_transport->iscsit_free_conn(conn);
+
+	iscsit_put_transport(conn->conn_transport);
+
 	conn->thread_set = NULL;
 
 	pr_debug("Moving to TARG_CONN_STATE_FREE.\n");

drivers/target/iscsi/iscsi_target_core.h

@@ -60,7 +60,7 @@
 
 #define ISCSI_IOV_DATA_BUFFER		5
 
-enum tpg_np_network_transport_table {
+enum iscsit_transport_type {
 	ISCSI_TCP				= 0,
 	ISCSI_SCTP_TCP				= 1,
 	ISCSI_SCTP_UDP				= 2,
@@ -503,6 +503,7 @@ struct iscsi_conn {
 	u16			login_port;
 	u16			local_port;
 	int			net_size;
+	int			login_family;
 	u32			auth_id;
 	u32			conn_flags;
 	/* Used for iscsi_tx_login_rsp() */
@@ -562,9 +563,12 @@ struct iscsi_conn {
 	struct list_head	immed_queue_list;
 	struct list_head	response_queue_list;
 	struct iscsi_conn_ops	*conn_ops;
+	struct iscsi_login	*conn_login;
+	struct iscsit_transport *conn_transport;
 	struct iscsi_param_list	*param_list;
 	/* Used for per connection auth state machine */
 	void			*auth_protocol;
+	void			*context;
 	struct iscsi_login_thread_s *login_thread;
 	struct iscsi_portal_group *tpg;
 	/* Pointer to parent session */
@@ -663,6 +667,8 @@ struct iscsi_login {
 	u8 first_request;
 	u8 version_min;
 	u8 version_max;
+	u8 login_complete;
+	u8 login_failed;
 	char isid[6];
 	u32 cmd_sn;
 	itt_t init_task_tag;
@@ -670,10 +676,11 @@ struct iscsi_login {
 	u32 rsp_length;
 	u16 cid;
 	u16 tsih;
-	char *req;
-	char *rsp;
+	char req[ISCSI_HDR_LEN];
+	char rsp[ISCSI_HDR_LEN];
 	char *req_buf;
 	char *rsp_buf;
+	struct iscsi_conn *conn;
 } ____cacheline_aligned;
 
 struct iscsi_node_attrib {
@@ -754,6 +761,8 @@ struct iscsi_np {
 	struct task_struct	*np_thread;
 	struct timer_list	np_login_timer;
 	struct iscsi_portal_group *np_login_tpg;
+	void			*np_context;
+	struct iscsit_transport *np_transport;
 	struct list_head	np_list;
 } ____cacheline_aligned;
 

drivers/target/iscsi/iscsi_target_login.h

@@ -4,8 +4,14 @@
 extern int iscsi_login_setup_crypto(struct iscsi_conn *);
 extern int iscsi_check_for_session_reinstatement(struct iscsi_conn *);
 extern int iscsi_login_post_auth_non_zero_tsih(struct iscsi_conn *, u16, u32);
+extern int iscsit_setup_np(struct iscsi_np *,
+				struct __kernel_sockaddr_storage *);
 extern int iscsi_target_setup_login_socket(struct iscsi_np *,
 				struct __kernel_sockaddr_storage *);
+extern int iscsit_accept_np(struct iscsi_np *, struct iscsi_conn *);
+extern int iscsit_get_login_rx(struct iscsi_conn *, struct iscsi_login *);
+extern int iscsit_put_login_tx(struct iscsi_conn *, struct iscsi_login *, u32);
+extern void iscsit_free_conn(struct iscsi_np *, struct iscsi_conn *);
 extern int iscsi_target_login_thread(void *);
 extern int iscsi_login_disable_FIM_keys(struct iscsi_param_list *, struct iscsi_conn *);
 

drivers/target/iscsi/iscsi_target_nego.c

@@ -22,6 +22,7 @@
 #include <scsi/iscsi_proto.h>
 #include <target/target_core_base.h>
 #include <target/target_core_fabric.h>
+#include <target/iscsi/iscsi_transport.h>
 
 #include "iscsi_target_core.h"
 #include "iscsi_target_parameters.h"
@@ -169,7 +170,7 @@ static void iscsi_remove_failed_auth_entry(struct iscsi_conn *conn)
 	kfree(conn->auth_protocol);
 }
 
-static int iscsi_target_check_login_request(
+int iscsi_target_check_login_request(
 	struct iscsi_conn *conn,
 	struct iscsi_login *login)
 {
@@ -352,11 +353,8 @@ static int iscsi_target_do_tx_login_io(struct iscsi_conn *conn, struct iscsi_log
 
 	padding = ((-login->rsp_length) & 3);
 
-	if (iscsi_login_tx_data(
-			conn,
-			login->rsp,
-			login->rsp_buf,
-			login->rsp_length + padding) < 0)
+	if (conn->conn_transport->iscsit_put_login_tx(conn, login,
+					login->rsp_length + padding) < 0)
 		return -1;
 
 	login->rsp_length		= 0;
@@ -368,72 +366,12 @@ static int iscsi_target_do_tx_login_io(struct iscsi_conn *conn, struct iscsi_log
 	return 0;
 }
 
-static int iscsi_target_do_rx_login_io(struct iscsi_conn *conn, struct iscsi_login *login)
-{
-	u32 padding = 0, payload_length;
-	struct iscsi_login_req *login_req;
-
-	if (iscsi_login_rx_data(conn, login->req, ISCSI_HDR_LEN) < 0)
-		return -1;
-
-	login_req = (struct iscsi_login_req *) login->req;
-	payload_length			= ntoh24(login_req->dlength);
-
-	pr_debug("Got Login Command, Flags 0x%02x, ITT: 0x%08x,"
-		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, CID: %hu, Length: %u\n",
-		 login_req->flags, login_req->itt, login_req->cmdsn,
-		 login_req->exp_statsn, login_req->cid, payload_length);
-
-	if (iscsi_target_check_login_request(conn, login) < 0)
-		return -1;
-
-	padding = ((-payload_length) & 3);
-	memset(login->req_buf, 0, MAX_KEY_VALUE_PAIRS);
-
-	if (iscsi_login_rx_data(
-			conn,
-			login->req_buf,
-			payload_length + padding) < 0)
-		return -1;
-
-	return 0;
-}
-
 static int iscsi_target_do_login_io(struct iscsi_conn *conn, struct iscsi_login *login)
 {
 	if (iscsi_target_do_tx_login_io(conn, login) < 0)
 		return -1;
 
-	if (iscsi_target_do_rx_login_io(conn, login) < 0)
-		return -1;
-
-	return 0;
-}
-
-static int iscsi_target_get_initial_payload(
-	struct iscsi_conn *conn,
-	struct iscsi_login *login)
-{
-	u32 padding = 0, payload_length;
-	struct iscsi_login_req *login_req;
-
-	login_req = (struct iscsi_login_req *) login->req;
-	payload_length = ntoh24(login_req->dlength);
-
-	pr_debug("Got Login Command, Flags 0x%02x, ITT: 0x%08x,"
-		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, Length: %u\n",
-		login_req->flags, login_req->itt, login_req->cmdsn,
-		login_req->exp_statsn, payload_length);
-
-	if (iscsi_target_check_login_request(conn, login) < 0)
-		return -1;
-
-	padding = ((-payload_length) & 3);
-
-	if (iscsi_login_rx_data(
-			conn,
-			login->req_buf,
-			payload_length + padding) < 0)
+	if (conn->conn_transport->iscsit_get_login_rx(conn, login) < 0)
 		return -1;
 
 	return 0;
@@ -693,6 +631,7 @@ static int iscsi_target_do_login(struct iscsi_conn *conn, struct iscsi_login *lo
 				return -1;
 			if (login_rsp->flags & ISCSI_FLAG_LOGIN_TRANSIT) {
 				login->tsih = conn->sess->tsih;
+				login->login_complete = 1;
 				if (iscsi_target_do_tx_login_io(conn,
 						login) < 0)
 					return -1;
@@ -736,7 +675,7 @@ static void iscsi_initiatorname_tolower(
 /*
  * Processes the first Login Request..
  */
-static int iscsi_target_locate_portal(
+int iscsi_target_locate_portal(
 	struct iscsi_np *np,
 	struct iscsi_conn *conn,
 	struct iscsi_login *login)
@@ -798,6 +737,8 @@ static int iscsi_target_locate_portal(
 		start += strlen(key) + strlen(value) + 2;
 	}
 
+	printk("i_buf: %s, s_buf: %s, t_buf: %s\n", i_buf, s_buf, t_buf);
+
 	/*
 	 * See 5.3.  Login Phase.
 	 */
@@ -956,100 +897,30 @@ static int iscsi_target_locate_portal(
 	return ret;
 }
 
-struct iscsi_login *iscsi_target_init_negotiation(
-	struct iscsi_np *np,
-	struct iscsi_conn *conn,
-	char *login_pdu)
-{
-	struct iscsi_login *login;
-
-	login = kzalloc(sizeof(struct iscsi_login), GFP_KERNEL);
-	if (!login) {
-		pr_err("Unable to allocate memory for struct iscsi_login.\n");
-		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
-				ISCSI_LOGIN_STATUS_NO_RESOURCES);
-		return NULL;
-	}
-
-	login->req = kmemdup(login_pdu, ISCSI_HDR_LEN, GFP_KERNEL);
-	if (!login->req) {
-		pr_err("Unable to allocate memory for Login Request.\n");
-		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
-				ISCSI_LOGIN_STATUS_NO_RESOURCES);
-		goto out;
-	}
-
-	login->req_buf = kzalloc(MAX_KEY_VALUE_PAIRS, GFP_KERNEL);
-	if (!login->req_buf) {
-		pr_err("Unable to allocate memory for response buffer.\n");
-		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
-				ISCSI_LOGIN_STATUS_NO_RESOURCES);
-		goto out;
-	}
-	/*
-	 * SessionType: Discovery
-	 *
-	 *	Locates Default Portal
-	 *
-	 * SessionType: Normal
-	 *
-	 *	Locates Target Portal from NP -> Target IQN
-	 */
-	if (iscsi_target_locate_portal(np, conn, login) < 0) {
-		goto out;
-	}
-
-	return login;
-out:
-	kfree(login->req);
-	kfree(login->req_buf);
-	kfree(login);
-
-	return NULL;
-}
-
 int iscsi_target_start_negotiation(
 	struct iscsi_login *login,
 	struct iscsi_conn *conn)
 {
-	int ret = -1;
-
-	login->rsp = kzalloc(ISCSI_HDR_LEN, GFP_KERNEL);
-	if (!login->rsp) {
-		pr_err("Unable to allocate memory for"
-				" Login Response.\n");
-		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
-				ISCSI_LOGIN_STATUS_NO_RESOURCES);
-		ret = -1;
-		goto out;
-	}
-
-	login->rsp_buf = kzalloc(MAX_KEY_VALUE_PAIRS, GFP_KERNEL);
-	if (!login->rsp_buf) {
-		pr_err("Unable to allocate memory for"
-			" request buffer.\n");
-		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
-				ISCSI_LOGIN_STATUS_NO_RESOURCES);
-		ret = -1;
-		goto out;
-	}
+	int ret;
 
 	ret = iscsi_target_do_login(conn, login);
-out:
 	if (ret != 0)
 		iscsi_remove_failed_auth_entry(conn);
 
-	iscsi_target_nego_release(login, conn);
+	iscsi_target_nego_release(conn);
 	return ret;
 }
 
-void iscsi_target_nego_release(
-	struct iscsi_login *login,
-	struct iscsi_conn *conn)
+void iscsi_target_nego_release(struct iscsi_conn *conn)
 {
-	kfree(login->req);
-	kfree(login->rsp);
+	struct iscsi_login *login = conn->conn_login;
+
+	if (!login)
+		return;
+
 	kfree(login->req_buf);
 	kfree(login->rsp_buf);
 	kfree(login);
+
+	conn->conn_login = NULL;
 }

drivers/target/iscsi/iscsi_target_nego.h

@@ -7,11 +7,14 @@
 extern void convert_null_to_semi(char *, int);
 extern int extract_param(const char *, const char *, unsigned int, char *,
 		unsigned char *);
-extern struct iscsi_login *iscsi_target_init_negotiation(
-		struct iscsi_np *, struct iscsi_conn *, char *);
+extern int iscsi_target_check_login_request(struct iscsi_conn *,
+		struct iscsi_login *);
+extern int iscsi_target_get_initial_payload(struct iscsi_conn *,
+		struct iscsi_login *);
+extern int iscsi_target_locate_portal(struct iscsi_np *, struct iscsi_conn *,
+		struct iscsi_login *);
 extern int iscsi_target_start_negotiation(
 		struct iscsi_login *, struct iscsi_conn *);
-extern void iscsi_target_nego_release(
-		struct iscsi_login *, struct iscsi_conn *);
+extern void iscsi_target_nego_release(struct iscsi_conn *);
 
 #endif /* ISCSI_TARGET_NEGO_H */

drivers/target/iscsi/iscsi_target_parameters.c

@@ -59,7 +59,7 @@ int iscsi_login_tx_data(
 	char *text_buf,
 	int text_length)
 {
-	int length, tx_sent;
+	int length, tx_sent, iov_cnt = 1;
 	struct kvec iov[2];
 
 	length = (ISCSI_HDR_LEN + text_length);
@@ -67,8 +67,12 @@ int iscsi_login_tx_data(
 	memset(&iov[0], 0, 2 * sizeof(struct kvec));
 	iov[0].iov_len		= ISCSI_HDR_LEN;
 	iov[0].iov_base		= pdu_buf;
-	iov[1].iov_len		= text_length;
-	iov[1].iov_base		= text_buf;
+
+	if (text_buf && text_length) {
+		iov[1].iov_len	= text_length;
+		iov[1].iov_base	= text_buf;
+		iov_cnt++;
+	}
 
 	/*
 	 * Initial Marker-less Interval.
@@ -77,7 +81,7 @@ int iscsi_login_tx_data(
 	 */
 	conn->if_marker += length;
 
-	tx_sent = tx_data(conn, &iov[0], 2, length);
+	tx_sent = tx_data(conn, &iov[0], iov_cnt, length);
 	if (tx_sent != length) {
 		pr_err("tx_data returned %d, expecting %d.\n",
 				tx_sent, length);

drivers/target/iscsi/iscsi_target_tpg.c

@@ -31,6 +31,8 @@
 #include "iscsi_target.h"
 #include "iscsi_target_parameters.h"
 
+#include <target/iscsi/iscsi_transport.h>
+
 struct iscsi_portal_group *iscsit_alloc_portal_group(struct iscsi_tiqn *tiqn, u16 tpgt)
 {
 	struct iscsi_portal_group *tpg;
@@ -508,7 +510,7 @@ struct iscsi_tpg_np *iscsit_tpg_add_network_portal(
 
 	pr_debug("CORE[%s] - Added Network Portal: %s:%hu,%hu on %s\n",
 		tpg->tpg_tiqn->tiqn, np->np_ip, np->np_port, tpg->tpgt,
-		(np->np_network_transport == ISCSI_TCP) ? "TCP" : "SCTP");
+		np->np_transport->name);
 
 	return tpg_np;
 }
@@ -522,7 +524,7 @@ static int iscsit_tpg_release_np(
 
 	pr_debug("CORE[%s] - Removed Network Portal: %s:%hu,%hu on %s\n",
 		tpg->tpg_tiqn->tiqn, np->np_ip, np->np_port, tpg->tpgt,
-		(np->np_network_transport == ISCSI_TCP) ? "TCP" : "SCTP");
+		np->np_transport->name);
 
 	tpg_np->tpg_np = NULL;
 	tpg_np->tpg = NULL;

drivers/target/iscsi/iscsi_target_util.c

@@ -24,6 +24,7 @@
 #include <target/target_core_base.h>
 #include <target/target_core_fabric.h>
 #include <target/target_core_configfs.h>
+#include <target/iscsi/iscsi_transport.h>
 
 #include "iscsi_target_core.h"
 #include "iscsi_target_parameters.h"
@@ -1226,34 +1227,19 @@ int iscsit_fe_sendpage_sg(
  */
 int iscsit_tx_login_rsp(struct iscsi_conn *conn, u8 status_class, u8 status_detail)
 {
-	u8 iscsi_hdr[ISCSI_HDR_LEN];
-	int err;
-	struct kvec iov;
 	struct iscsi_login_rsp *hdr;
+	struct iscsi_login *login = conn->conn_login;
 
+	login->login_failed = 1;
 	iscsit_collect_login_stats(conn, status_class, status_detail);
 
-	memset(&iov, 0, sizeof(struct kvec));
-	memset(&iscsi_hdr, 0x0, ISCSI_HDR_LEN);
-
-	hdr	= (struct iscsi_login_rsp *)&iscsi_hdr;
+	hdr	= (struct iscsi_login_rsp *)&login->rsp[0];
 	hdr->opcode		= ISCSI_OP_LOGIN_RSP;
 	hdr->status_class	= status_class;
 	hdr->status_detail	= status_detail;
 	hdr->itt		= conn->login_itt;
 
-	iov.iov_base		= &iscsi_hdr;
-	iov.iov_len		= ISCSI_HDR_LEN;
-
-	PRINT_BUFF(iscsi_hdr, ISCSI_HDR_LEN);
-
-	err = tx_data(conn, &iov, 1, ISCSI_HDR_LEN);
-	if (err != ISCSI_HDR_LEN) {
-		pr_err("tx_data returned less than expected\n");
-		return -1;
-	}
-
-	return 0;
+	return conn->conn_transport->iscsit_put_login_tx(conn, login, 0);
 }
 
 void iscsit_print_session_params(struct iscsi_session *sess)
@@ -1432,7 +1418,8 @@ void iscsit_collect_login_stats(
 		strcpy(ls->last_intr_fail_name,
 		       (intrname ? intrname->value : "Unknown"));
 
-		ls->last_intr_fail_ip_family = conn->sock->sk->sk_family;
+		ls->last_intr_fail_ip_family = conn->login_family;
+
 		snprintf(ls->last_intr_fail_ip_addr, IPV6_ADDRESS_SPACE,
 				"%s", conn->login_ip);
 		ls->last_fail_time = get_jiffies_64();